El Niño is Causing an Unprecedented Shift in Rain Patterns

El Niño is bringing an unprecedented shift in rain patterns. Now, NASA researchers are creating a visualization of these patterns to show exactly what they look like across the United States.

"During an El Niño, the precipitation averaged out over the entire globe doesn't change that much, but there can be big changes to where it happens," said George Huffman, one of the researchers, in a news release. "You end up with this interesting observation where you get both floods and droughts just by taking the usual precipitation pattern and doing a shift."

El Niño is a natural weather phenomenon that occurs every two to seven years. It's created through a shift in wind and ocean circulation; in normal, non-El Niño years, Pacific trade winds near the equator blow from east to west, moving warm surface water with them. But during an El Niño, trade winds move from west to east from Southeast Asia to South America. This moves warm water to the eastern tropical Pacific Ocean; the warm ocean water evaporates and falls as precipitation over nearby regions.

"Observing rainfall in an El Niño year is especially interesting because the prevailing precipitation patterns change, often in extreme ways," said Dalia Krschbaum, one of the researchers, in a news release. "Some areas become wetter. Some areas become drier. By seeing the whole globe, we are able to better understand how the precipitation is impacting different areas."

The southern area of the United States, including central California, across Texas and to Florida is experiencing wetter-than-average conditions. These conditions are expected to continue through June.

The findings reveal a bit more about this weather pattern, and show what kind of weather conditions we may face in the future.